JP7271611B2 - Test strips and test strip reading methods - Google Patents

Description

Generally, the present invention relates to optical analysis of one or more analytes applied to test strips.

FIG. 1 shows a conventional specimen test strip 100 with reaction areas 102 . Reaction region 102 contains a reagent that reacts with an analyte in a specimen sample, such as glucose in a blood sample. When the specimen sample reaches reaction area 102, reaction area 102 changes color depending on the properties of the analyte, such as glucose in blood. The user visually compares the drawing 104 with the color of the reaction area 102 to correlate the color of the reaction area 102 with the properties of the analyte. Also, the user inserts the specimen test strip 100 into the scale to optically measure the properties of the sample.

According to one aspect of the present disclosure, a specimen test strip for testing a property of an analyte in a specimen sample includes a reaction area configured to receive the specimen sample, and after receiving the specimen sample, the reaction area. A color calibration area configured to measure color is provided. In some embodiments, multiple reaction areas are provided, each configured to detect a different range of analyte characteristic values.

According to another aspect of the present disclosure, a method for a computer with an imaging device for reading a specimen test strip is provided for detecting properties of an analyte in a specimen sample. In some embodiments, the method comprises capturing images of one or more specimen test strips, each image including response areas and color calibration areas of the test strip. In these embodiments, the method further comprises measuring the color of the reaction area from the one or more images based on the color calibration area and relating the color of the reaction area to the characteristic value of the analyte.

In some embodiments, a method is provided comprising capturing at least two images of a specimen test strip, each image including a reaction area. The method further comprises determining a change in color intensity of the responsive area from the image and measuring the difference in time when the image is captured. The method also includes correlating the change in color intensity with the time-varying property value of the analyte.

In some embodiments, a method is provided comprising capturing a first image of a specimen test strip. The image has response areas, each response area configured to detect a different range of analyte characteristic values. The method further comprises selecting one of the reaction areas and associating the selected reaction area with the characteristic value of the analyte.

1 shows a specimen test strip according to the prior art; 1 illustrates a specimen test strip with reaction areas, color calibration areas, and temperature measurement areas in accordance with one or more examples of the present disclosure; 1 illustrates a specimen test strip with reaction areas, color calibration areas, and temperature measurement areas in accordance with one or more examples of the present disclosure; 4A-4B illustrate placement of reaction areas and color calibration areas in one or more examples of the present disclosure. 4A-4B illustrate placement of reaction areas and color calibration areas in one or more examples of the present disclosure. FIG. 11 illustrates a portion of a specimen test strip with timer zone capillaries in accordance with one or more examples of the present disclosure; FIG. 4 illustrates a specimen test strip with a response area and a timer area, in accordance with one or more examples of the present disclosure; 4 is a flowchart of a method for a computer executing a diagnostic application to measure and read a specimen test strip, in accordance with one or more examples of the present disclosure; FIG. 10 is a graph illustrating curves plotting analyte property values as changes in color parameters over time, in accordance with one or more examples of the present disclosure; FIG. FIG. 4 is a flow chart of a method for a computer to quickly read specimen test strips and run diagnostic applications using different calculations in accordance with one or more examples of the present disclosure; FIG. FIG. 10 is a flowchart of a method for a computer executing a diagnostic application for tracking a user's dietary restrictions according to analyte characteristics, in accordance with one or more examples of the present disclosure; FIG. FIG. 2 graphically depicts the relationship between diet, time and analyte signature values for one or more days in accordance with one or more examples of the present disclosure. 1 illustrates a specimen test strip that includes a series of reaction areas for detecting different ranges of analyte property values in a specimen sample, in accordance with one or more examples of the present disclosure; 13B shows the specimen test strip of FIG. 13A after holding specimen samples having different analyte property values, in accordance with one or more examples of the present disclosure; 13B shows the specimen test strip of FIG. 13A after holding specimen samples having different analyte property values, in accordance with one or more examples of the present disclosure; 13B shows the specimen test strip of FIG. 13A after holding specimen samples having different analyte property values, in accordance with one or more examples of the present disclosure; 1 illustrates a specimen test strip that includes a series of reaction areas for detecting different ranges of analyte property values in a specimen sample, in accordance with one or more examples of the present disclosure; 1 illustrates a specimen test strip that includes a series of reaction areas that detect different ranges of analyte property values in a specimen sample, in accordance with one or more examples of the present disclosure; 1 illustrates a specimen test strip that includes a series of reaction areas that detect different ranges of analyte property values in a specimen sample, in accordance with one or more examples of the present disclosure; 4 is a flowchart of a method for a computer executing a diagnostic application to read a specimen test strip with multiple response areas that detect different ranges of analyte property values, in accordance with one or more examples of the present disclosure; . 4 shows sample test strips under different exposures to sharpen details of certain reaction areas, in accordance with one or more examples of the present disclosure. 4 shows sample test strips under different exposures to sharpen details of certain reaction areas, in accordance with one or more examples of the present disclosure. 1 illustrates a specimen test strip including multiple reaction areas for detecting different analyte characteristic values, in accordance with one or more examples of the present disclosure; 1 is a cross-sectional view of a specimen test strip, in accordance with one or more examples of the present disclosure; FIG. FIG. 10 is a graph illustrating a curve plotting a change in a first color over time for a characteristic value of a first analyte, in accordance with one or more examples of the present disclosure; FIG. FIG. 10 is a graph illustrating a curve plotting a second color change over time for a characteristic value of a second analyte, in accordance with one or more examples of the present disclosure; FIG.

FIG. 2 illustrates an embodiment of a specimen test strip 200 in accordance with one or more examples of the present disclosure. Specimen test strip 200 has a reaction area 202 for receiving a specimen sample. The reaction area 202 contains reagents that chemically react with the analytes in the specimen sample to produce one or more color parameters proportional to the characteristic values of the analytes in the specimen sample. In some embodiments, the one or more color parameters comprise the color or color and color intensity of the responsive area 202 . In one example, the color is the tone of the reaction area 202 and the color intensity is the lightness of the reaction area 202 . Hue and lightness are color elements in the Hue, Saturation, and Lightness (HSL) color space, which are the number of red, green, and blue (RGB) pixels captured by the camera. For convenience, color and color intensity are collectively referred to as color. A reagent may be a specific analyte and may comprise one or more enzymes, one or more antibodies, or one or more dyes. For example, reagents for testing glucose in blood may include glucose oxidase, heteropolyacid, and tetrazylamine sodium nitrate.

In one example, the specimen test strip 200 has a color calibration area 204 of which it is part. In one example, color calibration area 204 is used to measure the color of response area 202 under conditions of varying brightness. In such an example, color calibration area 204 may be a color chart having an arrangement of known color samples. In another example, color calibration area 204 is used to correct the test color of reaction area 202 to remove the effects of lighting conditions. In such an example, color calibration area 204 may be a gray card with a known reference value (eg, 18%) to serve as a white balance reference value for color correction. Gray card 204 may also serve as an exposure reference when computer 210 captures image 212 of specimen test strip 200 . In one example, a color graph or gray card 204 is printed on the specimen test strip 200 .

In one example, color calibration area 204 is a dummy reaction area having one or more known colors. In use, the dummy reaction areas 204 retain the same color because they lack one or more enzymes, one or more antibodies, or one or more dyes. In another example, the dummy reaction areas 204 do not receive any specimen sample and thus maintain the same color.

In one example, sample test strip 200 has a temperature calibration region 206 that is a portion of sample test strip 200 along with reaction region 202 and color calibration region 204 . The temperature calibration area 206 changes color according to its temperature and is used to calibrate the color of the reaction area 202 since the chemical reaction between reagents and analytes is affected by the temperature of the specimen test strip 200 . In one example, the temperature calibration region 206 includes thermochromic dyes (e.g., spirolactones, fluoranes, spiropyrans or fulgits, etc.), organic materials such as leuco dyes, inorganic materials such as titanium dioxide, zinc oxide, or indium oxide, or It contains a thermochromic liquid crystal medium. In other embodiments, temperature calibration area 206 is a temperature indicating chip, mechanical device, or electromechanical device. Alternatively, or in addition to temperature calibration area 206, computer 210 may use a built-in temperature sensor to approximate or measure the temperature of reaction area 202. FIG.

By using imaging device 208 with computer 210 , the user captures images 212 of reaction area 202 , color calibration area 204 and/or temperature calibration area 206 . Imaging device 208 may be a camera, sensor, or other similar device, and computer 210 may be a smart phone, tablet computer, laptop, desktop, or other similar device. Computer 210 runs a diagnostic application that analyzes image 212 to determine the properties of the specimen from the color of reaction area 202 .

In one example, a diagnostic application determines the color of reaction area 202 using color calibration area 204 in image 212 . If color calibration area 204 is a color chart, the diagnostic application may compare the color of all or part of response area 202 with one of the known color samples of color calibration area 204 to determine the color of response area 202 . compare. The diagnostic application also processes image 212 until color graph 204 compares it to its known color and reads all or part of the color of reaction area 202 . If the color area 204 is a gray card, the diagnostic application processes the image 212 until the gray card 204 within the image 212 has the proper white balance and reads the color of the reaction area 202 .

In another example, the diagnostic application uses color calibration region 204 in image 212 to determine the color of reaction region 202 and temperature calibration region 206 in image 212 to correct the color. The diagnostic application determines the temperature of the specimen test strip 200 from the temperature calibration area 206 or the internal temperature sensor of the computer 210, and uses the known relationship between temperature and color of the reaction area 202 to determine the color of the reaction area. Correct for temperature. This relationship may be determined experimentally, mathematically, or both. A diagnostic application may use temperature calibration area 206 to perform color correction before or after any other corrections described in this disclosure.

In one example, the diagnostic application measures the illumination of image 212 before using color correction region 204 and temperature correction region 206 . A diagnostic application evaluates the illumination profile of the reaction area 202 to determine whether the illumination is uniform. The diagnostic application determines the lighting profile from the RGB values of at least two locations across the reaction area 202 or color calibration area 204 (eg, opposing corner pixels 506 and 508 in FIG. 5). When the illumination profile between the two locations is greater than the thresholded noise level (eg, when the illumination profile is twice the noise level), the illumination of the reaction area 202 is not uniform and the diagnostic application may reduce the illumination of the image 212 to to correct. In one example, the diagnostic application uses the following formula to correct the illumination of image 212:
New RGB＝i×(R(x,y), G(x,y), B(x,y))/(R est (x,y), G est (x,y), B est (x, y))
R(x,y), G(x,y), B(x,y) are the initial RGB values of the pixel, Rest(x,y), Gest(x,y), Best(x , y) are the evaluated RGB values of the illumination profile at the same pixel, and i is the maximum RGB value of the color of the reaction area.
For example, color calibration area 204 may include a white ring around reaction area 102 . In image 212, it is assumed that corner 506 has RGB values of (200,200,200) and corner 508 has RGB values of (100,100,100). Furthermore, the illumination profile is assumed to be linear. Based on these assumptions, the white point of center pixel 510 in reactive region 502 of FIG. 5 would have RGB values of (150,150,150). When the color of pixel 510 is not white and is instead said to have an RGB value of (125,75,75), the new RGB value of the center point is i×(125,75,75)/(150,150,150). , i is (255,255,255).

After one or more measurements described in this disclosure, the diagnostic application obtains pixel samples from the response area 202 (e.g., 50 to 100 pixels) and performs one or more chromatic parameters (e.g., color or color and color intensity) value. A diagnostic application averages the values of one or more color parameters and associates the one or more average color parameters with a characteristic value of the analyte (eg, glucose concentration level in blood).

In one example, reaction area 202, color calibration area 204, and temperature calibration area 206 are rectangular, and areas 204 and 206 are positioned adjacent the upper and lower sides of area 202, respectively. The reaction area 202, color calibration area 204, and temperature calibration area 206 may have other shapes and arrangements.

FIG. 3 illustrates a sample test strip 300 with different arrangements of reaction areas 302, color calibration areas 304, and temperature calibration areas 306, in accordance with one or more examples of the present disclosure. Color temperature region 306 is divided into regions 306A and 306B, and reaction region 302 is sandwiched from the left and right by regions 306A and 306B. The color calibration area 304 is adjacent to the lower side of the reaction area 302 and temperature calibration area 306 combination.

FIG. 4 illustrates an arrangement of reaction areas 402 and color calibration areas 404 in accordance with one or more examples of this disclosure. A color calibration area 404 surrounds the reaction area 402 . In one example, reaction area 402 has a circular shape and color calibration area 404 has a ring shape.

FIG. 5 illustrates an arrangement of reaction areas 502 and color calibration areas 504 in accordance with one or more examples of this disclosure. As in array 400 (FIG. 4), color calibration area 504 surrounds reaction area 502 . However, the reaction area 502 has a rectangular shape and the color calibration area 504 has a rectangular ring shape.

FIG. 6 illustrates a portion of a sample test strip 600 with timer capillary tubes in accordance with one or more examples of the present disclosure. Specimen test strip 600 represents a sample test strip with the reaction, color calibration and temperature measurement arrays described in this disclosure. Specimen test strip 600 has capillary inlet 604 , reaction capillary 606 and reaction area 608 . Reaction capillary 606 connects capillary inlet 604 to reaction region 608 . Timer capillary 602 is connected to capillary inlet 604 . Timer capillary 602 has a smaller cross-section than reaction capillary 606 . When specimen sample is received at capillary inlet 64, reaction capillary 606 conveys most of the specimen sample to reaction region 608 for detection of analyte properties. A small portion of the specimen sample travels along the timer capillary 602 and marks the elapsed time, so the processing of the specimen sample in the timer capillary 602 acts as a timer indicating when the specimen test strip 600 should be read. used.

FIG. 7 shows a specimen test strip 700 with a reaction area 702 and a timer area 704 in accordance with one or more embodiments of the present disclosure. Specimen test strip 700 shows a sample test strip 700 with all of the reaction area, color calibration and temperature measurement arrangements described in this disclosure. Timer area 704 is another reaction area for receiving specimen samples. For example, similar to sample test strip 600 , sample test strip 700 may have a reaction capillary connected to the capillary inlet and a timer capillary connecting the capillary inlet to timer region 704 . Since the response area 702 has a reagent that has a non-linear response to the specimen sample, while the timer area 704 has a reagent that has a nearly linear response to the specimen sample, the color change in the timer area 704 indicates when the specimen test strip 700 should be read. Used as a timer to indicate whether In one example, the timer area 704 is sealed and contains cobalt chloride (cobalt chloride) that changes from blue to pink in response to water particles in the specimen sample. The specimen test strip 700 may also have a color calibration area 706 and a temperature calibration area 708 .

In one example, the timer area 704 changes color in response to light once the specimen test strip 700 is removed from the opaque seal package. Timer area 704 linearly changes color in response to light to indicate the elapsed time that specimen test strip 700 has been removed from its package, and to indicate when specimen test strip 700 should be read. , the reaction time of the reaction area 702 may be predicted according to the specimen sample. The timer area 704 may be covered with a transparent protective film. In one example, timer region 704 may contain a photochromic dye such as azobenzene, salicylideneaniline, fulgites, spiropyran or spirooxazine.

In one example, timer area 704 changes color due to moisture once specimen test strip 700 is removed from the sealed package. The timer area 704 linearly changes color in response to moisture to indicate elapsed time as the specimen test strip 700 is removed from its package, and to indicate when the specimen test strip 700 should be read. The reaction time of the reaction area 702 may be predicted according to the specimen sample. The timer area 704 may be covered by a perforated transparent protective membrane that regulates exposure to moisture. In one example, timer region 704 contains cobalt chloride that changes from blue to pink.

Instead of using timer area 704, computer 210 may use a built-in timer to predict the reaction time of reaction area 702 in response to specimen samples.

FIG. 8 illustrates a computer (e.g., computer 210 of FIG. 2) running a diagnostic application to read a specimen test strip (e.g., specimen test strip 200 of FIG. 2) in accordance with one or more examples of the present disclosure. 8 is a flowchart of a method 800 for Although all methods described in this disclosure show blocks in sequential instructions, these blocks may be executed in parallel or with instructions different than those described herein. Also, various blocks may be consolidated into fewer blocks, divided into additional blocks, or eliminated based on the desired implementation. Method 800 may begin at block 802 .

At block 802 , computer 210 reads one or more images 212 of specimen test strip 200 . A plurality of images 212 are captured such that a stable image without shake is selected from the images 212 . Images 212 may be captured in rapid succession (eg, in continuous or rapid-fire mode) or frame by frame from video. In one example, each image 212 has a response area 202 and a color calibration area 204 . In another example, each image 212 may have temperature calibration regions 206 . In additional other examples, each image 212 may further have a timer region 602 or 704 .

When color calibration area 204 is a gray card, computer 210 may use color calibration area 204 as an exposure reference for capturing image 212 . Computer 210 may also use an object (eg, glass or human skin) near the specimen test strip with a reflectance of about 18% as an exposure reference. The computer 210 may automatically recognize the exposure reference value, or the user may manipulate the imager 208 to the exposure reference value to set the appropriate reference value.

In one example, computer 210 captures image 212 at the appropriate time after the specimen sample is placed on specimen test strip 200 . As previously mentioned, timer area 602 or 704 may indicate when image 212 should be captured. Computer 210 may monitor timer 602 or 704 and automatically capture image 212 , or a user may visually inspect timer 602 or 704 and operate imaging device 208 to capture image 212 . may Block 802 is followed by optional block 803 .

At option block 803, computer 210 selects a stable image 212 without shake. The diagnostic application may determine if the image is stable by using the built-in accelerometer to determine if the computer 210 was stable when the image 212 was captured. . The diagnostic application may use the built-in accelerometer to issue a warning if the user is not holding the computer 210 steady when the image 212 is about to be captured. Optional block 803 is followed by block 804 .

At block 804 computer 210 measures the illumination of responsive area 202 of image 212 . As previously described, computer 210 evaluates the illumination profile of image 212 and corrects the illumination of response area 202 of image 212 when the illumination is not uniform. Block 806 is followed by block 803 .

At block 806 , computer 210 determines the color of the responsive regions of image 212 . As noted above, computer 210 may determine the color of response area 202 based on color calibration area 204 in image 212 when color calibration area 204 is a color graph. Also, computer 210 simply reads the color of reaction area 202 from image 212 . Block 806 is followed by block 807 .

At block 807, computer 210 corrects the color of reaction area 202 based on one or more calibration areas. In one example, computer 210 corrects the color of reaction area 202 for white balance based on color calibration area 204 of image 212 when color calibration area 204 is a gray card. In one example, computer 210 corrects the color of response area 202 for temperature based on temperature calibration area 206 in image 212 . Note that the order of blocks 806 and 807 may be changed. Block 808 is followed by block 807 .

At block 808, computer 210 associates the color, or both color and color intensity, of sample pixels from response regions 202 in image 212 to analyze characteristic values (eg, glucose levels).

The rate of change of the color parameter of the reaction region 202 may depend on the property value of the analyte. For each analyte characteristic value, the rate of change of the color parameter may be plotted as a curve against time. FIG. 9 is a graph 900 illustrating three curves 902, 904 and 906 depicting changes in a color parameter (e.g., color intensity) versus time for three analyte characteristic values (e.g., three glucose levels). be. Each curve has a different slope over a time window (eg, time window 908) characteristic of the corresponding analyte characteristic value. Thereby, the difference in the values of at least two color parameters and the difference when the two values are taken may be used to ascertain the property of the corresponding analyte. The time window is positioned, eg, a few seconds earlier than the time to wait to read the previous specimen strip after the specimen sample is placed on the specimen strip 200, eg, 10 seconds or more.

FIG. 10 illustrates a computer (eg, FIG. 2) running a diagnostic application using different calculations to quickly read a specimen strip (eg, specimen strip 200 of FIG. 2) in accordance with one or more examples of the present disclosure. 10 is a flowchart of a method 1000 for the computer 210 of Method 1000 begins at block 1002 .

At block 1002 , computer 210 reads at least two images 212 of specimen test strip 200 in time window 908 . Images 212 may be images captured in rapid succession (eg, in continuous or rapid-fire mode) or frame by frame from video. For example, a first image 212 is captured at a first time and a second image 212 is captured at a second time. The time difference between the first time and the second time is calculated as a time window (eg, time window 908 shown in FIG. 9). Each image 212 has a reaction area 202 on the specimen test strip 200 . In one example, each image 212 may include color calibration areas 204 on specimen test strip 200 . In another example, each image further includes one or more additional calibration areas, such as temperature calibration area 206, on specimen test strip 200. FIG. In one example, computer 210 selects image 212 captured in time window 908 based on timer field 602 or 704 . Block 1004 is followed by block 1002 .

At block 1004, the computer 210 determines the color of the responsive regions 202 of each image 212 using all methods described in this disclosure, including illumination correction, color correction, and temperature correction. Block 1006 is followed by block 1004 .

At block 1006 , computer 210 determines from image 212 the change in color intensity of responsive area 202 . Block 1008 is followed by block 1006 .

At block 1008, computer 210 corrects for changes in color intensity to analyte property values. Computer 210 may use graph 900 or a mathematical representation of graph 900 to determine the property value of the analyte. In particular, computer 210 moves time window 908 along curves 902 , 904 and 906 . If the degree of change of the curve of the time window matches the degree of change of the response area 202, the response area 202 has the analytical characteristic value of that curve.

FIG. 11 is a flowchart of a method 1100 for a computer (eg, computer 210 of FIG. 2) executing a diagnostic application to track a user's diet according to analytical characteristics, in accordance with one or more examples of the present disclosure. be. Method 1100 begins at block 1102 .

At block 1102, computer 210 captures an image of the meal. Block 1104 is followed by block 1102 .

At block 1104, computer 210 records meal times. Block 1106 is followed by block 1104 .

At block 1106, the computer 210 associates meal with time and records this association against characteristic values determined substantially simultaneously. Analyte property values may be determined for use with any of the methods described in this disclosure. Blocks 1102, 1104 and 1106 may be repeated to track the user's diet over time. Block 1106 is followed by block 118 .

At block 1108, computer 210 displays the recorded associations over a computer network to another computer, such as a physician's computer, for treatment purposes. FIG. 12 provides a graphical representation correlating meal, time and analyte attribute values throughout the day in accordance with one or more examples of the present disclosure.

FIG. 13A illustrates a sample test strip 1300 in accordance with one or more examples of this disclosure. Specimen test strip 1300 has a series of response areas 1302A, 1302B, 1302C and 1302D (either as an overall "response area 1302" or as individual generic "response areas 1302"). Each reaction area 1302 is for detecting a different range of analyte characteristic values in the specimen sample. In one example, to detect glucose levels, response area 1302A detects 0 to 100 (mg/dl), response area 1302B detects 0 to 200 (mg/dl), and response area 1302C detects 0 to 400 mg/dl. dl, and reaction area 1302D detects 0 to 800 mg/dl. Reaction area 1302 concentrates one or more reagents at different locations to detect different ranges of analyte characteristic values. Also, the reaction areas 1302 have different reagents .

Specimen test strip 1300 may have a capillary inlet and a capillary that moves in contact with reaction area 1302 to carry the specimen sample. Specimen test strip 1300 may also have an extended area that overlies and contacts reaction area 1302 to apply sample to reaction area 1302 . A user may manually spread the sample over the example reaction area 1302 without special configuration to transport the sample to the reaction area 1302 . Specimen test strip 1300 may further include color calibration area 1304 and temperature calibration area 1306 .

FIG. 13A shows a specimen test strip 1300 in a pre-test state. FIG. 13B shows a specimen test strip 1300 holding a specimen sample of 150 mg/dl glucose in accordance with one or more examples of the present disclosure. Since glucose is more concentrated than the extent of reaction area 1302A, it has a hypersaturated color and is not used to determine glucose levels. However, reaction areas 1302B, 1302C and 1302D may also be used. The color of responsive area 1302B has better saturation and is therefore read better than responsive areas 1302C and 1302D.

FIG. 13C shows a specimen test strip 1300 holding a specimen sample of 300 mg/dl glucose, in accordance with one or more examples of the present disclosure. Since glucose is more concentrated than the areas of reaction regions 1302A and 1302B, they are oversaturated and they are not used to determine glucose levels. However, reaction areas 1302C and 1302D may be used. The color of responsive area 1302C has good saturation and is therefore read better than responsive area 1302D.

FIG. 13D shows a specimen test strip 1300 holding a specimen sample of 600 mg/dl glucose, in accordance with one or more examples of the present disclosure. Since glucose is more concentrated than the areas of response areas 1302A, 1302B and 1302C, they are hypersaturated colors and are not used to determine glucose levels. The color of the reaction area 1302D is well saturated and is used to determine the glucose level.

In one example, the reaction regions 1302 are rectangular and arranged collinearly to have a generally rectangular outline . Other shapes and arrangements of reaction areas 1302 are possible.

FIG. 14 illustrates a specimen test strip 1400 with different arrangements for reaction areas 1402A, 1402B, 1402C and 1402D (collectively "response areas 1402") in accordance with one or more examples of the present disclosure. In specimen test strip 1400, reaction areas 1402 are arranged to have a square outer contour . Similar to specimen test strip 1300 , specimen test strip 1400 may have structure for conveying a sample to reaction area 1402 or allowing a user to manually spread sample across reaction area 1402 .

FIG. 15 illustrates a specimen test strip 1500 with different arrangements for reaction areas 1502A, 1502B, 1502C and 1502D (collectively "response areas 1502") in accordance with one or more examples of the present disclosure. In sample test strip 1500, reaction sub-areas 1502 are triangular and arranged to have a square outline. Similar to specimen test strip 1300, specimen test strip 1500 may include structure for conveying a sample to the reaction area or may be manually extended beyond reaction area 1502 by the user.

FIG. 16 illustrates a specimen test strip 1600 with different arrangements for reaction areas 1602A, 1602B, 1602C and 1602D (collectively, "response areas 1602") in accordance with one or more examples of the present disclosure. In sample test strip 1600 , capillary inlet 1604 is connected to reaction area 1602 by capillary tube 1606 . Reaction areas 1602 are the same distance from capillary inlet 1604 and are evenly spaced around capillary inlet 1604 .

FIG. 17 illustrates a sample test strip (eg, sample test strip 1300 of FIG. 13) with multiple response areas for detecting different ranges of analyte property values, in accordance with one or more examples of the present disclosure. 17 is a flowchart of a method 1700 for a computer (eg, computer 210 of FIG. 2) executing a diagnostic application to read. Method 1700 begins at block 170 .

At block 1702 , computer 210 captures an image of specimen test strip 1300 . The image has a reaction area 1302 . As mentioned above, each reaction area 1302 is for detecting a different range of analyte characteristic values. Computer 210 may determine the color of each reaction area 1302 using any of the methods described in this disclosure. Block 1702 continues to block 1704 .

At block 1704, computer 210 selects a responsive area 1302 of appropriate saturation. Computer 210 examines reaction areas 1302 from the one with the smallest extent to the one with the largest extent. When the average RGB value of a reaction area 1302 is close to the noise level (eg, ˜10), indicating that the concentration of analyte is above its detection limit, computer 210 examines the next reaction area 1302. . This process continues until computer 210 selects a response region 1302 whose average RGB value is greater than the noise level. Block 1704 continues to block 1706 .

At block 1706, computer 210 associates the color or color intensity of the selected reaction area 1302 with the analyte characteristic value.

Method 1700 may be extended by taking multiple images of specimen test strip 1300 at multiple exposures in one or more examples of the present disclosure. FIG. 18 shows images 1802, 1804 and 1806 of 1/60, 1/30 and 1/15 specimen test strips 1300, respectively, in accordance with one or more examples of the present disclosure. At one extreme, image 1802 is underexposed to reveal details in one or more reaction areas that detect higher densities (e.g., reaction area 1302D), such that the sensitivity of these reaction areas is reduced. increase. At the other extreme, image 1806 has been overexposed to reveal details of one or more reaction areas to detect lower densities (e.g., reaction area 1302B) so that these reaction areas are sensitivity increases. If the exposure is between the extremes, image 184 will reveal details in one or more of the reactive areas to detect intermediate densities, thus increasing the sensitivity of these reactive areas.

Computer 210 may select one of images 1802, 1804 and 1806 based on the average RGB values of all of the responsive regions 1302 of each image. The average RGB value of all reactive regions 1302 in all images is either too low (e.g. <30) or too high (e.g. >240), indicating an inappropriate exposure time for this image. Then computer 210 selects another image.

Instead of adjusting exposure, method 1700 may be extended by taking multiple images of specimen test strip 1300 at multiple illumination intensities in one or more examples of the present disclosure. FIG. 19 shows images 1902, 1904 and 1906 of a specimen test strip 1300 at low, medium and high flash intensities, respectively, in accordance with one or more examples of the present disclosure. At one extreme, image 1902 is under a low illumination intensity that highlights the details of one or more reaction areas to detect lower densities (e.g., reaction area 1302A), such that the sensitivity of these reaction areas is reduced. increase. At the other extreme, image 1906 is under a high illumination intensity that details one or more reaction areas to detect higher densities (e.g., reaction area 1302D), such that the sensitivity of these reaction areas is reduced. increase. Intermediate illumination intensities cause image 1904 to detail one or more reaction areas to detect intermediate densities (eg, reaction area 1302C), thereby increasing the sensitivity of these reaction areas.

In this mode, computer 210 may test the illumination source (eg, flash) that previously captured images 1902, 1904 and 1906 to ensure that it is working properly. For example, computer 210 activates the flash at least once and uses the change in detected intensity to determine whether the flash is activated.

Computer 210 may select one of images 1902, 1904 and 1906 based on the average RGB values of all or part of the responsive area 1302 of each image. When the average RGB value of the responsive area 1302 of the image is too low (eg, <30) or too high (eg, >240), indicating that the illumination intensity of this image is inadequate, the computer 210 image.

FIG. 20 illustrates a sample test strip 2000, in accordance with one or more examples of the present disclosure. The specimen test strip 2000 has multiple reaction areas for detecting characteristic values of different analytes. In one example, the specimen test strip 2000 includes a reaction area 2002 for detecting a property of a first analyte in the specimen sample and a reaction area 2004 (eg, two analytes) for detecting a property of a second analyte in the specimen sample. three reaction areas 2004) and a reaction area 2006 (eg, three reaction areas 2006) for detecting properties of a third analyte in the specimen sample. Similar to the response areas 1302 shown in FIG. 13A, each of the multiple response areas 2004 detects a different range of second analyte property values and each of the multiple response areas 2006 detects a different third analyte property value. Detect range.

In one example, one analyte in a specimen sample is known to affect the detection of other analytes. For example, reaction area 2006 detects glucose in a blood sample and reaction area 2004 detects hematocrit (HCT) levels in a blood sample. HCT levels may be detected directly or indirectly (ie, by determining levels of other substances in a blood sample). A diagnostic application determines HCT levels and corrects glucose levels using a known relationship between HCT and glucose levels. This relationship may be determined experimentally, by calculation, or both. A diagnostic application may perform HCT corrections before and after all other corrections described in this disclosure.

Computer 210 may determine HCT levels in other ways from sample test strips. FIG. 21 is a cross-sectional view of a specimen test strip 2100 in accordance with one or more examples of the present disclosure. In specimen test strip 2100, a hole is provided in the passageway of the blood sample, light is shone on the blood sample, and the resulting light color is related to HCT level. In one example, sample test strip 2100 comprises capillary inlet 2102 , capillary 2104 connected to capillary inlet 2102 and reaction area 2106 connected to capillary 2104 . A hole 2108 is formed in capillary tube 2104 . A top opening 2110 of the hole 2108 is covered with a transparent film 2112 and a bottom opening 2114 is covered with a transparent film 2116 . Computer 210 transmits light through hole 2108 and takes the color of hole 2108 through which the light passes and relates it to HCT level, depending on the percentage of red blood cells in the blood. In another example, film 2116 is more reflective than film 2112 . A portion of the light is reflected or scattered at top aperture 2110 and captured by computer 210 to determine HCT levels.

In another example, a rectangular piece of material that filters red blood cells and absorbs lymph fluid is provided on the specimen test strip. HCT levels are then related to the amount of lymph fluid absorbed and determined from the distance a blood sample travels on a strip of paper.

Instead of using a timer region separate from the reaction region (e.g., timer region 602 or 704), method 800 uses a second color element in the reaction region to detect time and , may be extended by using the first color element of the reaction area to detect properties of the analyte.

FIG. 22 plots changes in the first color element (e.g., red) of the response region over time for a characteristic value of an analyte (e.g., glucose level in blood) in one or more examples of the present disclosure. Fig. 2200 is a graph illustrating curves; As shown, the curve of the first color element quickly settles to a constant value and thus may be used to indicate each value of the property of the analyte.

FIG. 23 is a graph 2300 illustrating a curve plotting changes in a second color component (e.g., blue color component) of a response region over time for a characteristic value of an analyte, in accordance with one or more examples of the present disclosure. . As can be seen, the curve of the second color element changes over time, so that when the first color element is read to determine the property value of the analyte (i.e., when the first color element stabilizes after) can be used as a timer to indicate In one example, at block 802 of method 800, computer 210 captures a number of images 212 and determines when the second color element indicates the appropriate time to read the first color element and, at that time, a characteristic value of the analyte. It may be determined whether to read the first color element to do so.

The test strips, systems and methods disclosed herein can be used to detect the presence or concentration of certain analytes such as, but not limited to, glucose, cholesterol, uric acid, troponin I, ketones, proteins, nitrites, and white blood cells. May be used for testing. Various fluids such as, but not limited to, blood, interstitial fluid, urine, saliva, and other bodily fluids may be tested.

As noted above, various embodiments of the present disclosure have been described for purposes of illustration, and it will be appreciated that various modifications may be made without departing from the scope and spirit of the present disclosure. deaf. Also, the various embodiments described herein are not intended to be so limiting, but are within the scope and intent presented by the present invention.

Claims (6)

capturing a first image of a specimen test strip, said first image comprising a plurality of response areas each configured to detect a different range of characteristic values of the analyte;
selecting a suitable chroma response area of the plurality of response areas;
associating the selected response area with an analyte characteristic value;
A method for a computer equipped with an imaging device for reading a specimen test strip to detect properties of an analyte in a specimen sample comprising: 4. The step of selecting one of the plurality of response areas of appropriate saturation comprises selecting a response area having an average RGB value of the response areas greater than a noise level. Item 1. The method according to item 1 . capturing a second image of the specimen test strip under different exposure conditions than the first image;
selecting the second image;
2. The method of claim 1 , further comprising: 4. The method of claim 3 , wherein the first image has an average RGB value of the responsive area that is less than or greater than the corresponding threshold. capturing a second image of the specimen test strip under a different illumination than the first image;
2. The method of claim 1 , further comprising selecting the second image. 6. The method of claim 5 , wherein the first image has an average RGB value of the responsive area that is less than or greater than the corresponding threshold.

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